Rotational comb drive z-stage

ABSTRACT

A device may have an outer frame, a platform, and a plurality of actuators configured to move the platform with respect to the outer frame. Each of the actuators may have a movable frame and a fixed frame. A motion control mechanism may be configured to permit movement of the platform in a desired direction with respect to the outer frame and inhibit rotation of the platform with respect to the outer frame.

BACKGROUND

1. Technical Field

This disclosure generally relates to actuators and more particularlyrelates, for example, to MEMS actuators with motion control that aresuitable for use in miniature cameras or other devices.

2. Related Art

Actuators for use in miniature cameras and other devices are well known.Such actuators typically comprise voice coils that are used to move alens for focusing, zooming, or optical image stabilization.

Miniature cameras are used in a variety of different electronic devices.For example, miniature cameras are commonly used in cellular telephones,laptop computers, and surveillance devices. Miniature cameras may havemany other applications.

It is frequently desirable to reduce the size of miniature cameras. Asthe size of electronic devices continues to be reduced, the size ofminiature cameras that are part of such electronic devices musttypically be reduced as well.

Further, it is desirable to enhance the shock resistance of suchminiature cameras. As the size of miniature cameras is reduced, smaller,more delicate components must often be utilized in their construction.Since such consumer products are typically subject to substantial abuse,such as rough handling and dropping, the components of miniature camerasmust be protected from the shock that is associated with such abuse.

SUMMARY

According to an embodiment, a device may comprise an outer frame, aplatform, and a plurality of actuators configured to move the platformwith respect to the outer frame. Each of the actuators may have amovable frame and a fixed frame. A motion control mechanism may beconfigured to permit movement of the platform in a desired directionwith respect to the outer frame and inhibit rotation of the platformwith respect to the outer frame.

According to an embodiment, a system may comprise an outer frame, aplatform, an optical element attached to the platform, and a pluralityof actuators configured to move the platform with respect to the outerframe. Each of the actuators may comprise a movable frame and a fixedframe. A motion control mechanism may be configured to permit movementof the platform in a desired direction with respect to the outer frameand inhibit rotation of the platform with respect to the outer frame.The permitted movement and the inhibited rotation may constrain movementof the optical element to desired movement thereof.

According to an embodiment, a method may comprise interconnecting anouter frame and a platform with a plurality of actuators configured tofacilitate movement of the platform with respect to the outer frame andinterconnecting the outer frame and the platform with a motion controlmechanism configured to move the platform with respect to the outerframe while inhibiting rotation of the platform with respect to theouter frame.

According to an embodiment, a method may comprise moving a platform withrespect to an outer frame using a plurality of actuators, permittingmovement of the platform in a desired direction with respect to theouter frame, and inhibiting rotation of the platform with respect to theouter frame using a motion control mechanism.

The scope of the disclosure is defined by the claims, which areincorporated into this section by reference. A more completeunderstanding of embodiments will be afforded to those skilled in theart, as well as a realization of additional advantages thereof, by aconsideration of the following detailed description of one or moreembodiments. Reference will be made to the appended sheets of drawingsthat will first be described briefly.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates an electronic device having an actuator device, inaccordance with an embodiment.

FIG. 2 illustrates a miniature camera having a lens barrel, inaccordance with an embodiment.

FIG. 3A illustrates the lens barrel having an actuator module disposedtherein, in accordance with an embodiment.

FIG. 3B illustrates the lens barrel and an actuator module in anexploded view, in accordance with an embodiment.

FIG. 4 illustrates the actuator module having the actuator devicedisposed therein, in accordance with an embodiment.

FIG. 5A illustrates a top view of the actuator device, in accordancewith an embodiment.

FIG. 5B illustrates a top view of the actuator device, in accordancewith an embodiment.

FIG. 6A illustrates a portion of the actuator device, in accordance withan embodiment.

FIG. 6B illustrates a portion of the actuator device, in accordance withan embodiment.

FIG. 6C illustrates a portion of a platform, in accordance with anembodiment.

FIG. 6D illustrates a bottom view of a movable lens positioned formounting to the actuator device, in accordance with an embodiment.

FIG. 6E illustrates a side view of the movable lens mounted to theactuator device, in accordance with an embodiment.

FIG. 7 illustrates portions of the actuator device, in accordance withan embodiment.

FIG. 8 illustrates a bottom view of the actuator device in a deployedconfiguration, in accordance with an embodiment.

FIG. 9A illustrates a portion of the actuator device in a deployedconfiguration without any voltage applied thereto, in accordance with anembodiment.

FIG. 9B illustrates a portion of the actuator device in a deployedconfiguration with a small voltage applied thereto, in accordance withan embodiment.

FIG. 9C illustrates a portion of the actuator device in a deployedconfiguration with a maximum voltage applied thereto, in accordance withan embodiment.

FIG. 10 illustrates a lateral snubber assembly, in accordance with anembodiment.

FIG. 11 illustrates a hinge flexure and a motion control torsionalflexure, in accordance with an embodiment.

FIG. 12 illustrates an inner motion control hinge, in accordance with anembodiment.

FIG. 13 illustrates a cantilever flexure, in accordance with anembodiment.

FIG. 14 illustrates a serpentine contact flexure and a deploymenttorsional flexure, in accordance with an embodiment.

FIG. 15 illustrates a top view of a deployment stop, in accordance withan embodiment.

FIG. 16 illustrates a bottom view of the deployment stop, in accordancewith an embodiment.

FIG. 17A illustrates a flap damper, in accordance with an embodiment.

FIG. 17B illustrates a movable frame disposed between an upper modulecover and a lower module cover with no shock applied, in accordance withan embodiment.

FIG. 17C illustrates the movable frame disposed between the upper modulecover and the lower module cover with a shock applied, in accordancewith an embodiment.

FIG. 17D illustrates a partial top view of another actuator device, inaccordance with an embodiment.

FIG. 17E illustrates an enlarged top view of the actuator device, inaccordance with an embodiment.

FIG. 17F illustrates an outer hinge flexure, a lateral snubber assembly,a single snubber flap and an interlocking snubber flaps feature of theactuator device, in accordance with an embodiment.

FIGS. 17G and 17H illustrate the outer hinge flexure, in accordance withan embodiment.

FIGS. 17I and 17J illustrate the lateral snubber assembly, in accordancewith an embodiment.

FIGS. 17K and 17L illustrate cross-sectional views of the single snubberflap and the interlocking snubber flaps, in accordance with anembodiment.

FIG. 17M illustrates a top view of the lateral snubber assembly, thesingle snubber flap and the interlocking snubber flaps, in accordancewith an embodiment.

FIG. 17N illustrates cross-sectional views of the single snubber flapand the interlocking snubber flaps, in accordance with an embodiment.

FIG. 18 illustrates a ball-in-socket snubber, in accordance with anembodiment.

FIG. 19 illustrates the ball-in-socket snubber and two frame hinges, inaccordance with an embodiment.

Embodiments of the disclosure and their advantages are best understoodby referring to the detailed description that follows. It should beappreciated that like reference numerals are used to identify likeelements illustrated in one or more of the figures.

DETAILED DESCRIPTION

An actuator device suitable for use in a wide variety of differentelectronic devices is disclosed in accordance with various embodiments.The actuator device may be adapted for use in a camera, such as aminiature camera, for example. The actuator device may be used to eithermanually or automatically focus the miniature camera. The actuatordevice may be used to zoom the miniature camera or to provide opticalimage stabilization for the miniature camera. The actuator device may beused to align the optics within the camera. The actuator device may beused for any other desired application in an electronic device or in anyother device.

In accordance with one or more embodiments, the actuator device maycomprise one or more MEMS actuators. The actuator device may be formedusing monolithic construction. The actuator device may be formed usingnon-monolithic construction.

The actuator device may be formed using contemporary fabricationtechniques, such as etching and micromachining, for example. Variousother fabrication techniques are contemplated.

The actuator device may be formed of silicon (e.g., single crystalsilicon and/or polycrystalline silicon). The actuator device may beformed of other semiconductors such as silicon, germanium, diamond, andgallium arsenide. The material of which the actuator device is formedmay be doped to obtain a desired conductivity thereof. The actuatordevice may be formed of a metal such as tungsten, titanium, germanium,aluminum, or nickel. Any desired combination of such materials may beused.

Motion control of the actuator device and/or items moved by the actuatordevice is disclosed in accordance with various embodiments. The motioncontrol may be used to facilitate a desired movement of an item whilemitigating undesired movement of the item. For example, the motioncontrol may be used to facilitate movement of a lens along an opticalaxis of the lens, while inhibiting other movements of the lens. Thus,the motion control may be used to facilitate movement of the lens insingle desired translational degree of freedom while inhibiting movementof the lens in all other translational degrees of freedom and whileinhibiting movement of the lens in all rotational degrees of freedom. Inanother example, the motion control may facilitate movement of the lensin all three translational degrees of freedom while inhibiting movementof the lens in all rotational degrees of freedom.

Thus, an enhanced miniature camera for standalone use and for use inelectronic devices may be provided. The miniature camera is suitable foruse in a wide variety of different electronic devices. For example, theminiature camera is suitable for use in electronic devices such ascellular telephones, laptop computers, televisions, handheld devices,and surveillance devices.

According to various embodiments, smaller size and enhanced shockresistance are provided. Enhanced fabrication techniques may be used toprovide these and other advantages. Such fabrication techniques mayadditionally enhance the overall quality and reliability of miniaturecameras while also substantially reducing the cost thereof.

FIG. 1 illustrates an electronic device 100 having an actuator device400, in accordance with an embodiment. As discussed herein, the actuatordevice 400 may have one or more actuators 550. In one embodiment, theactuators 550 may be MEMS actuators, such as electrostatic comb driveactuators. In one embodiment, the actuators 550 may be rotational combdrive actuators.

The electronic device 100 may have one or more actuators 550 for movingany desired component thereof. For example, the electronic device 100may have an optical device such as a miniature camera 101 that has theactuator 550 for moving optical elements such as one or more movablelenses 301 (shown in FIG. 2) that are adapted to provide focus, zoom,and/or image stabilization. The electronic device 100 may have anydesired number of the actuators 550 for performing any desiredfunctions.

The electronic device 100 may be a cellular telephone, a laptopcomputer, a surveillance device, or any other desired device. Theminiature camera 101 may be built into the electronic device 100, may beattached to the electronic device 100, or may be separate (e.g., remote)with respect to the electronic device 100.

FIG. 2 illustrates the miniature camera 101 having a lens barrel 200, inaccordance with an embodiment. The lens barrel 200 may contain one ormore optical elements, such as the movable lens 301, which may be movedby the actuator device 400 (shown in FIG. 1). The lens barrel 200 mayhave one or more optical elements which may be fixed. For example, thelens barrel 200 may contain one or more lenses, apertures (variable orfixed), shutters, mirrors (which may be flat, non-flat, powered, ornon-powered), prisms, spatial light modulators, diffraction gratings,lasers, LEDs and/or detectors. Any of these items may be fixed or may bemovable by the actuator device 400.

The actuator device 400 may move non-optical devices such as samplesthat are provided for scanning. The samples may be either biologicalsamples or non-biological samples. Examples of biological samplesinclude organisms, tissues, cells, and proteins. Examples ofnon-biological samples include solids, liquids, and gases. The actuatordevice 400 may be used to manipulate structures, light, sound, or anyother desired thing.

The optical elements may be partially or fully contained within the lensbarrel 200. The lens barrel 200 may have any desired shape, For example,the lens barrel 200 may be substantially round, triangular, rectangular,square, pentagonal, hexagonal, octagonal, or of any other shape orcross-sectional configuration. The lens barrel 200 may be eitherpermanently or removably attached to the miniature camera 101. The lensbarrel 200 may be defined by a portion of a housing of the miniaturecamera 101. The lens barrel 200 may be partially or completely disposedwithin the miniature camera 101.

FIG. 3A illustrates an actuator module 300 disposed within the lensbarrel 200, in accordance with an embodiment. The actuator module 300may contain the actuator device 400. The actuator device 400 may becompletely contained within the lens barrel 200, partially containedwithin the lens barrel 200, or completely outside of the lens barrel200. The actuator device 400 may be adapted to move optical elementscontained within the lens barrel 200, optical elements not containedwithin the lens barrel 200, and/or any other desired items.

FIG. 3B illustrates the lens barrel 200 and the actuator module 300 inan exploded view, in accordance with an embodiment. The movable lens 301is an example of an optical element that may be attached to the actuatordevice 400 and may be moved thereby. The actuator device 400 may bedisposed intermediate an upper module cover 401 and a lower module cover402.

Additional optical elements, such as fixed (e.g., stationary) lenses 302may be provided. The additional optical elements may facilitate focus,zoom, and/or optical image stabilization, for example. Any desirednumber and/or type of movable (such as via the actuator device 400) andfixed optical elements may be provided.

FIG. 4 illustrates the actuator module 300, in accordance with anembodiment. The actuator module 300 may be disposed partially orcompletely within the miniature camera 101. The actuator device 400 maybe disposed partially or completely within the actuator module 300. Forexample, the actuator device 400 may be sandwiched substantially betweenan upper module cover 401 and a lower module cover 402.

The actuator module 300 may have any desired shape. For example, theactuator module 300 may be substantially round, triangular, square,rectangular, pentagonal, hexagonal, octagonal, or of any other shape orcross-sectional configuration.

In one embodiment, the lens barrel 200 may be substantially round incross-sectional configuration and the actuator module 300 may besubstantially round in cross-sectional configuration. The use of asubstantially round lens barrel 200 and a substantially round actuatormodule 300 may facilitate an advantageous reduction in size. Thereduction in size may be facilitated, for example, because round lensesare commonly preferred. The use of a substantially round lens barrel 200and a substantially round actuator module 300 with round lenses tends toresult in a reduction of wasted volume and thus tends to facilitate areduction in size.

As discussed herein, one or more optical elements, such as the movablelens 301, may be disposed in an opening 405 (e.g., a hole) formed in theactuator module 300. Actuation of the actuators 550 may effect movementof the optical elements along their optical axis 410, for example. Thus,actuation of the actuators 550 may move one or more lenses to effectfocusing or zoom, for example.

The actuator module 300 may have cutouts 403 formed therein tofacilitate assembly of the actuator module 300 and alignment of theactuator device 400 contained therein. The cutouts 403 and/or electricalcontacts 404 partially disposed within the cutouts 403 may be used tofacilitate alignment of the actuator module 300 with respect to the lensbarrel 200.

FIG. 5A illustrates a top view of the actuator device 400 having theelectrical contacts 404, the opening 405, inner hinge flexures 501,kinematic mount flexures 502, movable frames 505, an outer frame 506,serpentine contact flexures 508, deployment torsional flexures 509,deployment stops 510, flap dampers 511, ball-in-socket snubbers 513,cantilever flexures 514, motion control torsional flexures 515, outerhinge flexures 516, a fixed frame 517, a platform 520, lens pads 521, apivot axis 525, the actuators 550, spaces 551, and blocks 552, inaccordance with an embodiment.

Blocks 552 (FIG. 5A) are shown to represent teeth 560 (see FIGS. 5B and7) of the actuator 550 in some figures. Those skilled in the art willappreciate that comb drives typically comprise a large number of verysmall teeth 560 that are difficult to show graphically on a drawing ofthis scale. For example, the actuator 550 may have between 1 and 10,000teeth on each side thereof and may have approximately 2,000 teeth oneach side thereof. Thus, in one embodiment, the blocks 552 may notrepresent the actual configuration of the teeth 560, but rather areshown in place of the teeth 560 to better illustrate the operation ofthe actuators 550, as discussed herein.

In accordance with an embodiment, the actuator device 400 may besubstantially hexagonal in shape. The hexagonal shape readilyfacilitates placement of the actuator device 400 within thesubstantially round lens barrel 200. The hexagonal shape alsofacilitates efficient use of wafer real estate. Other shapes arecontemplated.

The actuator device 400 may have a plurality of the actuators 550. Onlyone actuator 550 is illustrated in detail in FIG. 5A. The spaces 551 areshown in FIG. 5A for two additional actuators 550 that are notillustrated in detail. Thus, in one embodiment the actuator device 400may have three actuators 550 disposed in a substantially radiallysymmetric pattern about the opening 405 such that the actuators 550 arespaced approximately 120° apart from one another. The actuator device400 may have any desired number of the actuators 550 disposed in anydesired pattern. As further examples, the actuator device 400 may havetwo actuators 550 spaced approximately 180° apart from one another ormay have four actuators 550 spaced approximately 90° apart from oneanother.

As discussed herein, the actuators 550 may include one or more MEMSactuators, voice coil actuators, or any other desired type orcombination of types of actuators. For example, in one embodiment, eachactuator 550 may be a vertical rotational comb drive.

The actuators 550 may cooperate with one another to move a platform 520along the optical axis 410 (FIG. 3B), which in FIG. 5A is perpendicularto the plane of the actuator device 400. The actuators 550 may cooperatewith one another to move the platform 520 in a manner that maintains theplatform 520 substantially orthogonal with respect to the optical axis410 and in a manner that substantially mitigates rotation of theplatform 520.

Actuation of the actuators 550 is accomplished by the application of avoltage differential between adjacent teeth 560, represented by blocks552. Such actuation effects rotation of the actuators 550 to facilitatethe herein described movement of the platform 520.

In various embodiments, the platform 520 may be adapted substantially asa ring (e.g., as shown in FIG. 5A). Other shapes are contemplated. Theplatform 520 may have any desired shape.

Prior to deployment, the actuator device 400 may be a substantiallyplanar structure. For example, the actuator device 400 may besubstantially formed from a single, monolithic piece of material, suchas silicon. The actuator device 400 may be formed from a single die. Thedie may be approximately 4 to 5 millimeters across and approximately 150microns thick, for example.

The actuator device 400 may be formed by a MEMS technique, such asmilling or etching. A plurality of actuator devices 400 may be formedupon a single wafer. The overall shape or footprint of the actuatordevice 400 may be adapted to enhance the formation of a plurality of theactuator devices 400 on a single wafer.

Prior to operation, the fixed frame 517 of each actuator 550 may bedeployed to offset the adjacent pairs of teeth 560 represented by blocks552 with respect to one another, in accordance with an embodiment.Deployment may result in a substantially non-planar overallconfiguration of the actuator device 400. When deployed, each actuator550 may have a portion thereof (e.g., the fixed frame 517) extendingfrom the plane of the outer frame 506. The fixed frame 517 may extendfrom the plane of the outer frame 506 at an angle with respect thereto.Thus, when deployed, the fixed frame 517 may be substantiallyout-of-plane with respect to the outer frame 506.

Once deployed, the fixed frames 517 may be fixed or locked into positionsuch that they do not move further with respect to the outer frame 506,and are angularly offset or rotated with respect to the outer frame 506and with respect to the movable frame 505 (when the actuator 550 is notactuated). The fixed frames 517 may be mechanically fixed in position,adhesively bonded in position, or any desired combination ofmechanically fixed and adhesively bonded.

Actuation of the actuator 550 may cause the movable frame 505 to rotatetoward the deployed fixed frame 517 to effect desired movement of theplatform 520. Motion control torsional flexures 515 and outer hingeflexures 516 cooperate to facilitate motion controlled rotation of themovable frame 505, as discussed herein. The movable frame 505 rotatesabout the pivot axis 525.

FIG. 5B illustrates a top view of the actuator device 400 having teeth560 shown in the actuator 550 in place of the blocks 552 representativethereof, in accordance with an embodiment. The teeth 560 shown may beconsidered to be reduced in number and exaggerated in size for clarityin FIG. 5B.

FIG. 6A illustrates a top view of one of the actuators 550 having theinner hinge flexures 501, the ball-in-socket snubbers 513, the movableframe 505, the outer hinge flexures 516, the motion control torsionalflexures 515, the cantilever flexures 514, the fixed frame 517, thepivot axis 525, the serpentine contact flexure 508, the pseudokinematicmount and electrical contact 404, and the platform 520, in accordancewith an embodiment. FIG. 6A further illustrates a lateral snubberassembly 1001, which is further described herein.

The inner hinge flexure 501 cooperates with the cantilever flexure 514to transfer desired motion from the movable frame 505 to the platform520. Thus, actuation of the actuator 550 results in rotation of themovable frame 505, which in turn results in translation of the platform520, as discussed herein.

The movable frame 505 may pivot on the outer hinge flexures 516 in afashion similar to a door pivoting on its hinges. Upon the applicationof a shear force to the actuator device 400, one of the two outer hingeflexures 516 of the actuator 550 may be in tension while the outer hingeflexure 516 may be in compression. The two motion control torsionalflexures 515 tend to mitigate undesirable buckling of the outer hingeflexure 516 in such instances.

Each actuator may be substantially disposed within a motion controlmechanism that provides comparatively high lateral stiffness andcomparatively soft rotational stiffness. In one embodiment, the motioncontrol mechanism may have one or more (e.g., two) outer hinges flexures516 and may have one or more (e.g., two) motion control torsionalflexures 515. Thus, movement of the movable frame 505 may besubstantially constrained to desirable rotation thereof.

In one embodiment, the motion control mechanism for one actuator 550 maycomprise the outer frame 506, movable frame 505, the motion controltorsional flexures 515, the outer hinge flexures 516, the inner hingeflexures 501, the cantilever flexure 514, and the platform 520. In oneembodiment, the motion control mechanism may comprise all structuresthat tend to limit movement of the platform 520 to desired translationalmovement.

Each actuator 550 may be substantially contained within the motioncontrol mechanism to substantially limit competition for real estate onthe actuator device 400, in accordance with an embodiment. Since eachactuator 550 and its associated motion control mechanism occupysubstantially the same surface area of the actuator device 400, they donot compete for real estate. Thus, as the actuator 550 increases insize, its associated motion control mechanism may also increase in size.In certain embodiments, it is desirable to increase the size of anactuator 550 to increase the force provided thereby. In certainembodiments, it is desirable to also increase the size of the motioncontrol mechanism to maintain its ability to desirably limit movement ofthe platform 520. The movable frame 550 may be considered as a portionof the motion control mechanism.

FIG. 6B illustrates the actuator 550 showing the fixed frame 517 shadedfor clarity, in accordance with an embodiment. The shaded fixed frame517 may be deployed to a position out-of-plane of the actuator device400 and may be fixed in this deployed position.

The movable frame 505 may support moving portions of the actuator 550,such as some of the teeth 560 (see FIG. 7). The fixed frame 517 maysupport fixed portions of the actuator 550, such as others of the teeth560 (see FIG. 7). The application of a voltage to the actuator 550 maycause the movable frame 505 to rotate about the outer hinge flexures 516toward the fixed frame 517. Removal or reduction of the voltage maypermit a spring force applied by the inner hinge flexures 514, the outerhinge flexures 516 and the motion control torsional flexure 515 torotate the movable frame 505 away from the fixed frame 517. Sufficientclearance between the movable frame 505 and the fixed frame 517 may beprovided to accommodate such desired movement.

FIG. 6C illustrates a portion of the platform 520 having radialvariations 571, in accordance with an embodiment. In one embodiment, theradial variations 571 may be formed in the platform 520 to permit theplatform 520 to expand. The radial variations 571 may be angular bendsin the platform 520. Thus, an optical element such as the movable lens301 may be inserted into the opening 405 of the platform 520, which mayexpand to receive the movable lens 301 and which may grip the movablelens 301. The opening 405 may expand as the radial variations 571 of theplatform 520 deform (e.g., tend to straighten), so as to increase thecircumference of the opening 405.

FIG. 6D illustrates a perspective view of a movable lens positioned formounting to the actuator device 400 and FIG. 6E illustrates a side viewof the movable lens 301 attached to the actuator device 400, inaccordance with an embodiment. In one embodiment, the movable lens 301may be adhesively bonded to the platform 550, such as by adhesivelybonding standoffs 522 of the movable lens 301 to the lens pads 521. Forexample, epoxy 523 may be used to adhesively bond the movable lens 301to the platform 520. The movable lens 301 may be supported by the lenspad 521.

FIG. 7 illustrates a portion of the actuator 550 showing blocks 552superimposed over the teeth 560 of an actuator 550, in accordance withan embodiment. As discussed herein, the blocks 552 are representative ofthe teeth 560.

FIG. 8 illustrates a bottom perspective view of the actuator device 400in a deployed configuration, in accordance with an embodiment. In thedeployed configuration the unactuated movable frame 505 is substantiallyin-plane with respect to the outer frame 506 and the deployed fixedframe 517 is substantially out-of-plane with respect to the outer frame506 and the movable frame 505.

A voltage may be applied to each actuator 550 via the electricalcontacts 404. For example, two of the three contacts 404 may be used toapply a voltage from the lens barrel 200 to the actuator device 400. Thethird contact 404 may be unused or may be used to redundantly apply onepolarity of the voltage from the lens barrel 200 to the actuator device400.

Substantially the same voltage may be applied to the three actuators 550to result in substantially the same movement of the moving frames 505thereof. Application of substantially the same voltage to the threeactuators 550 may result in translation of the platform 520 with respectto the outer frame 506 such that the platform 520 remains substantiallyparallel to the outer frame 506. Thus, an optical element such as themovable lens 301 may be maintained in a desired alignment as the opticalelement is moved, such as along an optical axis 410 (FIG. 3B) thereof.

Substantially different voltages may be applied to the three actuators550 to result in substantially different movements of the moving frames505 thereof. Substantially different voltages may be applied to thethree actuators 550 using the three contacts 404 and a common return.Thus, each contact 404 may apply a separately controlled voltage to adedicated one of the three actuators 550.

The application of substantially different voltages to the threeactuators 550 may result in translation of the platform 520 with respectto the outer frame 506 such that the platform tilts substantially withrespect to the outer frame 506. Thus, when substantially differentvoltages are applied, the platform 520 does not necessarily remainsubstantially parallel to the outer frame. The application of differentvoltages to the three actuators 550 may be used to align the platform520 to the outer frame 506, for example. The application of differentvoltages to the three actuators 550 may be used to facilitate opticalimage stabilization or lens alignment, for example.

FIG. 9A illustrates a portion of the actuator device 400 in a deployedconfiguration without any voltage applied thereto, in accordance with anembodiment. Without any voltage applied to the actuator device 400, themovable frame 505 is substantially in-plane with respect to the outerframe 506 and the deployed fixed frame 517 is substantially out-of-planewith respect to the outer frame 506 and the movable frame 505.

FIG. 9B illustrates a portion of the actuator device 400 in a deployedconfiguration with a small voltage applied thereto, in accordance withan embodiment. With the small voltage applied, the movable frame 505 hasrotated toward the deployed fixed frame 517 and is in a partiallyactuated position.

FIG. 9C illustrates a portion of the actuator device 400 in a deployedconfiguration with a maximum voltage applied thereto, in accordance withan embodiment. As may be seen, the movable frame 505 has rotated furthertoward the deployed fixed frame 517 and is in a fully actuated position.

FIG. 10 illustrates a top view of a lateral snubber assembly 1001, inaccordance with an embodiment. The lateral snubber assembly 1001 mayhave a first snubber member 1002 and a second snubber member 1003. Thefirst snubber member 1002 may be formed upon the fixed frame 517 and thesecond snubber member may be formed upon the movable frame 505. Thefirst snubber member 1002 and the second snubber member 1003 maycooperate to inhibit undesirable lateral motion of the movable frame 505with respect to the fixed frame 517 (and consequently with respect tothe outer frame 506, as well) during shock or large accelerations. A gap“D” between the first snubber member 1002 and the second snubber member1003 may approximately 2-3 micrometers wide to limit such undesirablelateral motion.

FIG. 11 illustrates a perspective view of the motion control torsionalflexure 515 and the outer hinge flexure 516, in accordance with anembodiment. The motion control torsional flexure 515 and the outer hingeflexure 516 may be thinner than other portions of the actuator device400 to provide the desired stiffness of the motion control torsionalflexure 515 and the outer hinge flexure 516. For example, in oneembodiment the outer hinge flexures 516, the inner hinge flexures 501,and the motion control torsional flexures 515 may have a width ofapproximately 100 microns and a thickness of approximately 2-3 microns.

The motion control torsional flexure 515 may be located on the pivotaxis 525. In one embodiment, the pivot axis 525 is a line that connectsthe centers of the two outer hinge flexures 516. In one embodiment, thepivot axis 525 is the hinge line or axis about which the movable frame506 rotates.

FIG. 12 illustrates a perspective view of an inner hinge flexure 501, inaccordance with an embodiment. The inner hinge flexure 501 may bethinner than other portions of the actuator device 400 to provide thedesired stiffness of the inner hinge flexure 501. For example, in oneembodiment, the inner hinge flexure 501 may be approximately 500micrometers long, 60 micrometers wide, and 2-3 micrometers thick.

FIG. 13 illustrates a perspective view of a cantilever flexure 514having the inner hinge flexure 501, a first thinned section 1301, athicker section 1302, and a second thinned section 1303, in accordancewith an embodiment. The cantilever flexure 514 may be used to transfermovement of the movable frames 505 to the platform 520. The cantileverflexure 514 may be used to facilitate the conversion of rotation of themovable frames 505 into translation of the platform 520.

The inner hinge flexure 501 may bend to permit the movable frame 505 torotate while the platform 520 translates. The first thinned section 1301and the second thinned section 1303 may bend to permit a change indistance between the movable frame 505 and the platform 520 as themovable frame 505 transfers movement to the platform 520.

The cantilever flexure 514 may be thinner proximate the ends thereof andmay be thicker proximate the center thereof. Such configuration maydetermine a desired ratio of stiffnesses for the cantilever flexure 514.For example, it may be desirable to have a comparatively low stiffnessradially to compensate for the change in distance between the movableframes 505 and the platform 520 as the movable frame 505 transfersmovement to the platform 520.

FIG. 14 illustrates a perspective view of the serpentine contact flexure508 and the deployment torsional flexure 509, in accordance with anembodiment. The serpentine contact flexure 508 may facilitate electricalcontact between the electrical contacts 404 and the deployed fixedframe. The deployment torsional flexures 509 may facilitate rotation ofthe deployed fixed frame 517 with respect to the outer frame 506 duringdeployment.

FIG. 15 illustrates a perspective top view of a deployment stop 510showing that it does not contact an outer frame 506 on the top side whendeployed, in accordance with an embodiment. An epoxy 1501 may be appliedto the top surfaces of the deployment stop 510 and the outer frame 506to fix the deployment stop 510 into position with respect to the outerframe 506. Thus, the epoxy 1501 may fix the deployed fixed frame 517into position with respect to the outer frame 506. Various portions ofthe deployed fixed frame 517 may function as the deployment stops 517.For example, other portions of the deployed fixed frame 517 that abutthe outer frame 506 when the deployed fixed frame is deployed mayfunction as the deployment stops 510.

FIG. 16 illustrates a perspective bottom view of the deployment stop 510showing that it contacts the outer frame 506 on the bottom side whendeployed, in accordance with an embodiment. The epoxy 1501 may beapplied to the bottom surfaces of the deployment stop 510 and the outerframe 506 to fix the deployment stop 510 into position with respect tothe outer frame 506. The epoxy 1501 may be applied to both the topsurfaces and the bottom surfaces of the deployment stop 510 and theouter frame 506, if desired.

FIG. 17A illustrates a perspective view of a flap damper 511, inaccordance with an embodiment. The flap damper 511 is located where thedesirable relative motion during intended operation, (e.g., actuation)of actuators 550, is comparatively low and where the potentialundesirable relative motion during shock is comparatively high. Forexample, the flap damper 511 may be formed on the pivot axis 525.

A damping material 1701 may extend across a gap 1702 formed between theouter frame 506 and the movable frame 505. The damping material 1701 mayhave a high damping coefficient. For example, in one embodiment, thedamping material 1701 may have a damping coefficient of between 0.7 and0.9. For example, the damping material 1701 may have a dampingcoefficient of approximately 0.8. In one embodiment, the dampingmaterial 1701 may be an epoxy.

The damping material 1701 may readily permit the desired motion of themovable frame 505 relative to the outer frame 506. The damping material1701 may inhibit undesired motion of the movable frame 505 relative tothe outer frame 506 due to a shock. Thus, the damping material 1701 maypermit rotation of the movable frame 505 relative to the outer frame 506during actuation of the actuators 550 and may inhibit lateral motionand/or out of plane motion of the movable frame 505 relative to theouter frame 506 during a shock.

The flap damper 511 may have a flap 1706 that extends from the movableframe 505 and may have a flap 1707 that extends from the outer frame506. A gap 1702 may be formed between the flap 1706 and the flap 1707.

An extension 1708 may extend from the flap 1706 and/or an extension 1709may extend from the flap 1707. The extension 1708 and the extension 1709may extend the length of the gap 1702 such that more damping material1701 may be used than would be possible without the extension 1708and/or the extension 1709.

Trenches 1719 may be formed in flaps 1706 and/or 1707 and a trenchmaterial 1720 that is different from the material of the flaps 1706 and1707 may be deposited within the trenches 1719. For example, the flaps1706 and 1707 may be formed of single crystalline silicon and the trenchmaterial 1720 may be formed of polycrystalline silicon. Any desiredcombination of materials may be used for the flaps 1706 and 1707 and forthe trench material 1720, so as to achieve the desired stiffness of theflaps 1706 and 1707.

FIG. 17B illustrates the movable frame 505 disposed between the uppermodule cover 401 and the lower module cover 402 without a shock beingapplied thereto. In the absence of a shock, the movable frame 505remains in its unactuated position and the outer hinge flexure 516 isunbent.

FIG. 17C illustrates the movable frame 505 after it has been moved to aposition against the lower module cover 402 by a shock, such as may becaused by dropping the electronic device 100. Movement of the movableframe 505 may be limited or snubbed by the lower module housing 402 andundesirable double bending of the outer hinge flexure 516 may be limitedthereby. In a similar fashion, the upper module housing 401 may limitmovement of the movable frame 505 and double bending of the outer hingeflexure 516. Thus, undesirable stress within the outer hinge flexures516 may be mitigated.

FIGS. 17D-17H illustrate an alternative embodiment of an outer hingeflexure 1752. As illustrated in these figures, in some embodiments, theouter hinge flexures 1752 may be X-shaped for increased control of themotion of the moveable frame 505 in the lateral direction. The outerhinge flexures 516, 1752 may generally tend to bend, such as about acentral portion thereof, to facilitate movement of the moveable frame505 with respect to the outer frame 506. Other shapes are contemplated.For example, the outer hinge flexure 1752 can be shaped like a H, I, M,N, V, W, Y, or may have any other desired shape. Each outer hingeflexure 1752 can comprise any desired number of structures thatinterconnect the outer frame 506 and the movable frame 505. Thestructures may be interconnected or may not be interconnected. Thestructures may be substantially identical with respect to one another ormay be substantially different with respect to one another. Each outerhinge flexure 1752 may be substantially identical with respect to eachother hinge flexure 1752 or may be substantially different with respectthereto.

The outer hinge flexures 516, 1752 and any other structures may beformed by etching as discussed herein. The outer hinge flexure and anyouter structures may comprise single crystalline silicon,polycrystalline silicon, or any combination thereof.

FIGS. 17D-F and 17I-17N show an alternative embodiment of the lateralsnubber assembly 1754, another embodiment of which is disused withrespect to FIG. 10 herein. The lateral snubber assembly 1754 of FIGS.17D-F and 17I-17N generally has more rounded curves with respect to thelateral snubber assembly 1001 of FIG. 10.

FIGS. 17D-17F illustrate an alternative embodiment of an interlockingsnubber flaps feature 1756 useful for constraining both verticalmovement of a component, e.g., moveable component 505, in the ±Zdirections, as well as lateral movement thereof, i.e., in the ±X and/or±Y directions. As may be seen in the cross-sectional views of FIGS. 17K,17L and 17N, the structure of and methods for forming the interlockingflaps feature 1756 are similar to those of the interlocking flapsfeature 5000 discussed above in connection with FIGS. 49-53.

As illustrated in FIG. 17F, this interlocking flaps feature includes theformation of a pair of flaps 1756A and 1756B respectively extending frommoveable and fixed components 505 and 506 and over a correspondingshoulder 1762 formed on the other, opposing component. The flap 1756A onthe moveable component 505 limits motion of the moveable component 505in the −Z direction, and the flap 1756B on the fixed component 506limits motion of the moveable component 505 in the +Z direction.Additionally, as illustrated in FIGS. 17K, 17L and 17N, the gap 1760between the two components 505 and 506, which may be formed as discussedabove in connection with FIGS. 49A-49F, may limit motion of the moveablecomponent 505 in the ±X and/or ±Y directions.

As illustrated in FIG. 17M, the respective front ends of the flaps 1756Aand 1756B may define corners at the opposite ends thereof, and one ormore of the corners may incorporate elliptical fillets 1766.

As illustrated in FIGS. 17D-17L and FIGS. 17K-17N, a single snubber flap1758 may be provided for constraining lateral movement of a component,e.g., moveable component 505, in an actuator device 1750. For example,the snubber flap 1758, which in some embodiments may comprisepolysilicon, may extend from a fixed component, e.g., component 506, andtoward but not over, the moveable component 505 to limit motion of themoveable component 505 in the lateral, i.e., in the in the ±X and/or ±Ydirections. As illustrated in FIGS. 17K, 17L and 17N, the gap 1764between the fixed and moveable components 505 and 506 can be maderelatively larger than the gap 1768 between the snubber flap 1758 andthe moveable component 505, such that the snubber flap 1758 does notinterfere with normal rotational motion of the movable component 505,but does function to prevent unwanted lateral motion thereof.

FIG. 18 illustrates a ball-in-socket snubber 513, in accordance with anembodiment. The ball-in-socket snubber 513 may have a substantiallycylindrical ball 518 that is slidably disposed within a substantiallycomplimentary cylindrical socket 519. The ball-in-socket snubber 513permit desired movement of the platform 520 with respect to the outerframe 506 and limit other movement.

FIG. 19 illustrates a perspective view of the ball-in-socket 513 and twoframe hinges 526, in accordance with an embodiment. The frame hinges 526may be hinge flexures in the otherwise substantially rigid outer frame506. The frame hinges 526 permit the outer frame 506 to deformout-of-plane while maintained desired rigidity in-plane.

Although the actuator disclosed herein is described as a MEMS actuator,such description is by way of example only and not by way of limitation.Various embodiments may include non-MEMS actuators, components ofnon-MEMS actuators, and/or features of non-MEMS actuators.

Thus, an actuator suitable for use in a wide variety of differentelectronic devices may be provided. Motion control of the actuatorand/or items moved by the actuator may also be provided. As such, anenhanced miniature camera for use in electronic devices may be provided.

According to various embodiments, smaller size and enhanced shockresistance for miniature cameras are provided. Enhanced fabricationtechniques may be used to provide these and other advantages. Thus, suchfabrication techniques may additionally enhance the overall quality andreliability of miniature cameras while also substantially reducing thecost thereof.

Where applicable, the various components set forth herein may becombined into composite components and/or separated into sub-components.Where applicable, the ordering of various steps described herein may bechanged, combined into composite steps, and/or separated into sub-stepsto provide features described herein.

Embodiments described herein illustrate but do not limit the disclosure.It should also be understood that numerous modifications and variationsare possible in accordance with the principles of the disclosure.

1. A device comprising: an outer frame; a platform; a plurality ofactuators adapted to move the platform with respect to the outer frame,each of the actuators comprising a movable frame and a fixed frame; anda motion control mechanism adapted to permit movement of the platform ina desired direction with respect to the outer frame.
 2. The device asrecited in claim 1, wherein the motion control mechanism comprises aflexure interconnecting the movable frame of one of the actuators andthe platform.
 3. The device as recited in claim 2, wherein the flexureis adapted to bend in a plurality of different directions.
 4. The deviceas recited in claim 2, wherein the flexure is adapted to bend in onedirection to accommodate a varying angle between the movable frame ofthe one of the actuators and the platform and bend in a differentdirection to accommodate a varying distance between the movable frame ofthe one of the actuators and the platform.
 5. The device as recited inclaim 4, wherein the flexure is adapted to bend in the one direction andin the different direction to inhibit rotation of the platform withrespect to the outer frame.
 6. The device as recited in claim 1, whereinthe motion control mechanism comprises a flexure interconnecting themovable frame of the one of the actuators and the outer frame.
 7. Thedevice as recited in claim 1, wherein the motion control mechanismcomprises a hinge flexure and a torsional flexure interconnecting themovable frame of the one of the actuators and the outer frame.
 8. Thedevice as recited in claim 1, wherein the motion control mechanismcomprises a plurality of hinge flexures and a plurality of torsionalflexures interconnecting the movable frame of the one of the actuatorsand the outer frame.
 9. The device as recited in claim 8, wherein thehinge flexures and the torsional flexures substantially limit movementof the movable frame of the one of the actuators to a single degree offreedom, and wherein the single degree of freedom is rotation.
 10. Thedevice as recited in claim 9, wherein at least one of the hinge flexuresis X-shaped.
 11. The device as recited in claim 1, wherein the pluralityof actuators comprise three actuators.
 12. The device as recited inclaim 11, wherein the plurality of actuators are disposed in asubstantially radially symmetric configuration with respect to oneanother.
 13. The device as recited in claim 1, wherein the outer frame,the platform, and the plurality of actuators are formed by a MEMSprocess.
 14. The device as recited in claim 1, wherein the outer frame,the platform, and the plurality of actuators are formed of monolithicsilicon.
 15. The device as recited in claim 1, wherein the outer frameis substantially planar.
 16. The device as recited in claim 1, whereinthe platform is substantially planar.
 17. The device as recited in claim1, wherein the outer frame and the platform are disposed insubstantially parallel planes.
 18. The device as recited in claim 1,wherein the outer frame and the platform are substantially coplanar withrespect to one another prior to actuation of the actuators.
 19. Thedevice as recited in claim 1, wherein the actuators are rotationalactuators.
 20. The device as recited in claim 1, wherein the actuatorsare rotational comb drives.
 21. The device as recited in claim 1,wherein the platform comprises a ring adapted to expand to receive alens.
 22. The device as recited in claim 21, wherein: the ring comprisesradial variations to permit the ring to expand; and the platformcomprises a plurality of pads for supporting the lens.
 23. The device asrecited in claim 1, wherein the movement of the platform is atranslational movement.
 24. An electronic device comprising the deviceof claim
 1. 25. A system comprising: an outer frame; a platform; anoptical element attached to the platform; a plurality of actuatorsadapted to move the platform with respect to the outer frame, each ofthe actuators comprising a movable frame and a fixed frame; a motioncontrol mechanism adapted to permit movement of the platform in adesired direction with respect to the outer frame; and wherein thepermitted movement and the inhibited rotation constrain movement of theoptical element to desired movement thereof.
 26. A method comprising:interconnecting an outer frame and a platform with a plurality ofactuators adapted to facilitate movement of the platform with respect tothe outer frame; and interconnecting the outer frame and the platformwith a motion control mechanism adapted to move the platform withrespect to the outer frame.
 27. A method comprising: moving a platformwith respect to an outer frame using a plurality of actuators; andpermitting movement of the platform in a desired direction with respectto the outer frame using a motion control mechanism.